Biomechanics part 1 & 2 Flashcards
Discus, javelin and ski jumpers have an ________ shape. Where air pressure is ___ above and ____ below to create an upwards lift force
aerofoil, low, high
Creation of additional lift force on a projectile (due to movement of air from high to low pressure) is the b__________ p___________
bernoulli principle
Flight path symmetrical about it’s highest point caused by dominant force of weight is what type of flight path?
parabolic e.g. shot putt
Sporting example of a non-parabolic flight path is a s_______cock (badminton)
shuttlecock
Slice shot goes to the left or right?
Right (Slice-Rice)
The memory hook for planes and axis is?
Tuna, Smells, Fishy (Planes)
Lollies, Taste, Fruity (Axis)
Bernoulli principle. Air under low pressure travels at a ___ velocity
high
Backspin is an attacking or defensive shot?
Defensive-causes ball to float/travel further/longer flight path
Topspin is an attacking or defensive shot?
Attacking-causes ball to dip/comes down more quickly/shorter flight path
Aerofoil shapes create an __wards lift force
up
Track cyclists and F1 cars have an _______ aerofoil shape. Where air pressure is ____ above and ____ below.
inverted, high, low
Most favourable angle of release for a projectile to create lift is called the angle of a_____ ?
attack-45 degrees when starting height and landing height are same
A flight path asymmetrical about its highest point caused by a dominant force of air resistance is what type of flight path?
Non parabolic
Hook shot goes to the right or left?
Left (Hook-Look)
Spin (rotation) is created by an e________ force applied outside the centre of mass (CoM)
eccentric
Ice skating pirouette: during mid flight moment of inertia (resistance to rotation) is ____ and angular velocity is ____
low, high
What type of spin makes a ball dip and shoot forward off the surface?
Top spin
Sporting example of parabolic flight path is s___ p___
shot putt
Which of Newton’s laws states that a body continues in a state of rest or constant velocity unless acted on by an external force?
Newton’s first law- law of inertia
Bernoulli principle. Air under high pressure travels at ___ velocity
low
Describe shape of a parabolic flight path?
A flight path symmetrical about its highest point caused by the dominant force of weight e.g. shot
Downwards forces are created by i________ aerofoils
inverted
Bernoulli principle (apply to F1 car or track cyclist)-air travels at ? velocity and ? pressure below the cyclist. Above the F1 car or track cyclist air travels at ? velocity and ? pressure. This pushes the F1 car/cyclist into the ground creating grip.
high, low (below)
low, high (above)
What type of spin makes the ball ‘sit up’ and decelerate off the surface?
Back spin
Dominant force acting on a projectile during a non-parabolic flight path is a__ r_________
air resistance
Which of Newton’s Laws refers to a body’s change in momentum (acceleration) is proportional to the size and direction of the force applied.
Newton’s second law- law of acceleration
What is Centre of Mass?
Point at which weight appears to act/ where an object is balanced in all directions.
Newton’s law of angular motion states a rotating body will continue to turn abouts its a___ of r________ with constant a_______ m___________unless acted upon by an eccentic force
axis of rotation, angular momentum
Angular motion results from an ________ force applied outside the COM
Eccentric
Ice skating pirouette during landing phase, moment of inertia is ___ and angular velocity is ___
high , low
Dominant force acting on a projectile during a parabolic flight path is w_____
weight
When moment of inertia = low, angular velocity=?
High
When moment of inertia is high, angular velocity is ___
low
What happens to Centre Of Mass during the Fosbury Flop in high jump?
Take off = arms raised COM higher but within body
Flight = COM located outside the body, under the bar
Name the 4 factors affecting horizontal distance travelled by projectiles (ASHA)?
Angle of release
Speed of release
Height of release
Aerodynamics
Describe moment of inertia
Resistance of a body to change its rotation
Describe angular velocity
Rate of change in rotation (rate of spin)
Describe angular momentum
The quantity of rotation possessed
Name and describe the memory hook for use of technology (limb kinematics/force plates/wind tunnels) to optimise (maximise) performance in sport?
TRAINERS Positives T-Technique R-Rehabilitation A-Accurate data I-Information for analysis Negative N-Not available to most E-Expensive R-Results complicated S-Specialist training needed
Name the memory hook for the 3 axes of rotation? Give a sporting example for each axis.
Lollies, Taste, Fruity
L-Longitudinal (Longest = top to bottom-a trampolinist performing a full twist)
T-Transverse (Table football = side to side-a front somersault)
F-Fruity (Front to back-a cartwheel)
Name the force that opposes motion through the air?
Air resistance (N)
Name the force that opposes the motion of two surfaces in contact (anti-slipping force)?
Friction (N)
Name the force that is the gravitational pull of the earth on a body?
Weight (N)
Name the force that is the equal and opposite force exerted by a body in response to the action force placed upon it e.g. sprinter pushes foot against the starting blocks-starting blocks exert an equal and opposite force back
Reaction (N)
Using an ice skating jump with a pirouette describe what the ice skater does to create rotation. REMEMBER to describe what happens at:
- Take off
- Mid flight
- In preparation for landing/landing
TAKE-OFF-angular momentum is generated by the ice skater applying an eccentric force from the ice to the body. Rotation starts around the longitudinal axis. Mass is distributed away from the axis of rotation which means Moment of Inertia is high and Angular Velocity is low.
MID FLIGHT: mass is distributed close to the longitudinal axis. Moment of Inertia is low, Angular Velocity is high (the ice skater spins quickly)
IN PREP FOR LANDING/LANDING: mass is distributed away from longitudinal axis. Moment of Inertia is high and Angular Velocity is low (the ice skater slows spin for controlled landing). AS THEY LAND: the ice applies an eccentric force to the ice skater which removes the conserved quantity of angular momentum.
